ker@mtgzy.UUCP (k.e.roser) (03/12/86)
Well, another week has gone by and I still don't have a working 520ST. It has been in repair since January 16th. Would you believe that I sent the computer and power supply together along with a note stating the power supply was blown and they only fixed the computer. They sent me back a fixed (?) 520 and the same blown power supply. Thank goodness I checked the power supply before plugging it into the computer. I now have to send back the power supply and they will send back a new one. Note, I MUST send mine back first even though I was told the old black one will be replaced (supposedly they have a design problem that causes +5 to go to +15V). Therefore I assume it will take another week to get another supply, assuming they are available. A word of advise. I have been told that if you have the old black "brick" power supply for the 520ST (P/N CO70099-3) you can be in the same situation as me. There is a design problem that can cause the +5 volt supply to provide +15 volts. This extra voltage does not make the computer work three times faster (3 X 5 = 15). It puts you in the same position I am in. Your computer will have to take a trip to the local repair shop for an extended vacation, hopefully not > 2 months as in my case. The advise I've been given is to get ATARI to replace your old power supply with the newer model. Supposedly the old supply is a disaster waiting to happen. Again, let me emphasize I am repeating what I was told. This is not my opinion and do not claim originality for these claims.
knnngt@ukma.UUCP (Alan Kennington) (03/19/86)
***** Nobody knows the lines I've eaten - song title ***** It's about time I make another comment on the jolly black power supplies. A couple of days ago, my TOS ROM(s) blew. I deduced this from the fact that all went well with the old chips replaced. It took a week for the new chips to stop working. But I gather that these ROMs are really Eproms which happen to be opaque, which makes them somewhat vulnerable to the dreaded power supply surge. Now the people who told me about the power supply scandal have consequently informed me that a very simple test will determine whether the power supply is of the evil variety, without having to wait for disaster to visit. It seems that with zero load, a humble voltmeter will demonstrate the true nature of the thing. So this would indicate that the same fault that causes sub-optimal start-up characteristics also causes inappropriate response to zero load. If so, this would help prevent a lot of indecision about what to do with "the black power supplies".